Impulse sender



.lms, 1942. H, D H 2,268,859

IMPULSE SENDER Filed Sept. a, 1937 INVEN'IJOR HINRICH DOHLE ATTORNEY Patented Jan. 6, 1942 IMPULSE SENDER Hinrich Diihle, Berlin-Alt-Glienicke, Germany,

assignor to Telephon-Apparat Fabrik E. 'Zwietusch and Company, Berlin, Germany Application September 3, 1937, Serial No. 162,361 In'Germany September 5, 1936 6 Claims. (Cl. 177-480) This application -is an improvement of my previous application Serial Number 142,573, filed May 14, 1937, which describes a registering device whose elements consist of condensers which are charged difierently in accordance with the kind of switching operation to be effected and which by their discharge control the desired switching operation. The embodiment describes a numerical sender in which the switching operation to.

be performed consists of a numerical selection and impulses have to be transmitted in accordance with the selected number. ber of impulses transmitted is determined in that the discharge current controls the release period of a relay so that the number of impulses to be transmitted is determined by the duration of the release period of this relay. mode of operation requires a very accurate adjustment of the relay.

The present invention avoids such sensitive relays which are prejudicial to'the efficiency of the system. This is realized by the invention in that the determination of the state of charge of the registering condenser which is necessary'for controlling the impulse sender is efiected by the cooperation of an auxiliary condenser which causes the registering condenser to be discharged in stages and a device which characterizes the state of charge of the registering condenser. According to the invention the device which character izes the state of charge of the registering condenser consists of an electron tube whose grid is connected to. the registering condenser. The negative potential applied to the grid by the charged register condenser prevents the flow of anode current so that a supervisory relay which is disposed in the anode circuit and which controls the impulse sending device cannot operate until the registering condenser is discharged.

An embodiment of the invention is represented in the drawing. As in'the prior application the embodiment chosen is a numerical sender for contact 'IT: earth-'IT-3u-ly-X-battery. The numand Z are conventional slow acting relays, and it will be seen that the last-mentioned of t ese has two windings. In the same way as in he embodiment represented in theprior application six figure numbers can be registered and the corresponding impulse trains transmitted. The

mode of operation of the circuit is as follows:

On depressing one of the keys T0 to T9, for

example the key T3; the following operations take' place: First of all relays X pulls up over Over contact 3.: relays Y and Z operate. During the energizing period of relay Y charging current flows to the condenser Cl over resistance W13 in the following circuit: battery-T3-Wi3-lx-2y-lu- DII on a step ll-Cl-5x-earth. The condenser Cl is consequently charged in accordance with the key (T3) depressed. The requirement that three impulses shall be transmitted which is characterized by the depression of the key T3 is now registered by the charge on condenser Cl. Contact I y breaks the circuit for relay X. As soon therefore as contact 32: has reached the rest position the rotary magnet D is energized in the following circuit: earth-3x-3z-D-battery. Relay Zpossesses two windings Z1 and ZIIand is slow- 1 to-release. Contact 32 therefore breaks the energizing circuit for magnet D after a short time so that the wipers dl to dl are advanced one step. By the depression of a second key T0 to T9 the condenser C2 is now charged accordingly. The operations which have been described now take place again. At the end of the dialling the individual impulse trains corresponding to the battery. Relay B is switched on over contact Ia.

setting switches in telephone systems. The key contacts of the numerical sender are. indicated 1 by the reference TI! to T9. When one of these Relays A and B operateas an automatic intercondenser Cl is charged over contacts lb and 5b from the particular one of the registering contime interval under control of relays X and Y,

densers CI to C6 which is connected up over wiper DII. In position 6 of the stepping switch DII the condenser Cl is discharged to a definite level by the condenser Cl whose capacity is considerably less than the capacity of the registering condensers CI to C6.

With relay B in the rest position the auxiliary condenser 01 is connected over contacts lb and 5b to battery, the potential applied to the auxiliary condenser being such that 'when the relay energizes the charge on the auxiliary condenser is opposite in sense to the charge on the registering condensers. In, this way the charge in the registering, condenser is diminished by the charge on the auxiliary condenser. The auxiliary condenser is then charged by the registering condenser in accordance with the potential still limiting the, charge on the registering condenser.

, R, determined by the charge on the registering condenser, which controls the anode current. As

soon therefore'as the discharge of the registering condenser which is made to take place in stages by the auxiliarycondenser C! has reached a definite value relay H draws up and at contact 3h breaks the energizing circuit for relay A and thereby brings the interrupter comprising relays A and B to rest. In place of the electron tube It a grid control rectifier can be used. The slowto-release relay V energizes over contact 2a and at contact 21) operates the slow-to-release relay W. Relays V and W remain operated so long as relay A is operating as an interrupter. As soon as relay A-is permanently disconnected by contact 3h relays V and W fall back one after the other so that after contact 371. has been switched over relay Z operates over its winding ZII' in the following circuit: earth-4u-3h-3wZH and battery. The rotary magnet D energizes over contact 32. Contact d shortcircfiits winding ZII. Relay Z releases and thereby deenergizes the rotary magnet D. As soon as the stepping switch has been advanced to the next contact relay H releases since the next registering condenser which is still charged is connected to the grid of the tube R. The next registering condenser is discharged 'over the auxiliary condenser C1 in synchronism with the relay interrupter A/B until relay H energizes again. The switching opera tions are repeated until all the registering condensers have transmitted the condition characterized by their state of charge. In order to be, able to dial a call number consisting of fewer ,digits than six a blank key LT is provided by means of which the stepping switch D can be advanced. If for example a call number comprising four digits is dialled the key LT must be depressed twice at the end in order to set the impulse sender in operation in correspondence with four dialled digits. A release key.AT is provided by. means of which the impulse sender may be restored to normal at any timefrom any position.

It should: be mentioned that the invention is not limited in application to a numerical sender for telephone systems. It may be applied with advantage where a particular switching operation to be brought about by a switching measureis required not to operate immediately but only after the expiration'of a definite time or in dependence upon switching operations occu rring subsequently. The registering device can, for example, be used in register circuits for automatic telephone systems. By suitably adjusting the auxiliary condenser orby inserting a suitable timing element for the charging of the auxiliary condenser it is possible for the register to be used at thesame time as a translator. If for example the number 5 is selected by depressing the key 5 it can be brought about by suitably adjusting the auxiliary condenser C1 that by connecting the auxiliary condenser three times to the registering condenser in which the number 5 was registered, the latter is discharged to such an extent that only three impulses are transmitted. Thus in this case the number 5 has been translated into the number 3.

A further application of the invention is in control switches for dispatch systems in which registers are used, for example, in tubular conveyor systems. i

What isclaimed is:

1. In an impulse sender in which a digit is recorded as a quantity of charge upon a register condenser and subsequently transmitted. as one or more impulses, an impulse generator, an auxiliary condenser, means controlled by said generator to alternately charge said auxiliary condenser and connect same in series opp0sitionwith said register condenser to discharge said register condenser step by step, and means controlling the number of impulses generated by said impulse generator in accordance with the state of charge existing upon said register condenser.

2. An impulse sender as claimed in claim 1, wherein said last means includes a grid controlled gaseous conduction device the potential of whosegrid is determined by the state of charge existing upon said register condenser.

3. In an impulse sender for registering a digit as a quantity of charge on a register condenser and subsequently retransmitting the digit as oneor more impulses, a second condenser, means for repeatedly charging said second condenser to a predetermined potential and connecting said second condenser in series opposition With said register condenser to successively reduce the charge on said register condenser in substantially uniform steps to a predeterminedvalue, the number of steps required to reduce the charge on said register condenser to said predetermined value therefore being characteristic of the digit registered, and means for terminating said action established therein when the potential of saidof said last means when the charge on said register condenser has been reduced to' said predetermined value. v

4. In combination, a gaseous discharge device having a filament, a grid and a plate, two condensers, means for placing a variable initial charge upon the first of said condensers, means forconnecting said first condenser to the grid of said discharge device, means for reducing the potential of, said grid in steps by alternately charging the second of said condensers by a ,pre-

determined amount and connecting it in opposition with said first condenser, and aplate circuit for said discharge device having a current fiow grid is reduced to a predetermined value.

5. In combination. two condensers, means for placing a variable initial charge on the first of said condensers, means for alternately charging the second of said condensers and connecting same in opposition with said first condenser thereby to reduce thecharge on said first condenser in steps, and detector means sensitive to a particular value 0! charge on said first condenser and operated responsive to said charge on said first condenser reaching said particular value. v f

6. In combination; a condenser, means operated to connect said condenser in a circuit including a source of potential to establish a charge of a certain value on said condenser, a second condenser, means Ior connecting said second condenser in a. circuit including a source of potential to establish a charge of a certain value on said second .condenser and for then connecting said condensers in a circuit in opposition to each other to withdraw an increment of charge from 7 said first condenser, means for repeatedly op- 

